1. Field of the Invention
The present invention relates generally to storage libraries for handling and storing media elements such as cartridges and for reading and writing to the media elements using media element players such as drives. More particularly, the present invention relates to a self-contained robotics module which facilitates modular replacement and removal of media element handling robotics into and out of a storage library.
2. Background Art
An automated data storage library generally includes media storage elements such as cartridges, media element players such as drives, and media element handling components such as a media element handling robot assembly. The library includes individual cells which hold respective cartridges. The robot assembly includes a picker which is operable to move about the library and selectively load a cartridge from a cell into a drive. The picker is generally operable to remove cartridges from the cells and drives and load cartridges into the cells and drives.
Certain storage library designs enable the libraries to be expandable for capacity upgrades. Many storage library expansion solutions require complex installation techniques at the library user's site. Some solutions require costly robot assembly duplication, while other solutions require skilled personnel to link existing robot assemblies with the expansion mechanics. It would be desirable if storage library capacity expansion did not require manipulation, addition, modification, etc., to the robot assembly already part of the storage library.
In a typical storage library the hardware components of the robot assembly are distributed in various areas of the storage library. As such, if the robot assembly malfunctions then someone with a technical understanding of the storage library, such as a service engineer, is needed to locate and fix the malfunction. The service engineer is required because the storage library may need to be dismantled in order to find and fix the malfunction.
U.S. Pat. No. 5,870,245 discloses an example of a storage library in which media element handling robotics are distributed across various parts of the storage library. The disclosed storage library includes storage library modules vertically stacked within a rack. Each storage library module is fully enclosed within its own metal enclosure. The enclosures mount within respective spacings in the rack.
Inside its enclosure, each storage library module includes a drive shaft for moving a picker of the robot assembly within the storage library module. The rear of the enclosures are configured to form a U-shaped channel along their height. A pulley system placed within the U-shaped channel moves the picker to and from the drive shafts of the storage library modules in order to move the picker amongst the storage library modules.
As such, the robot assembly of the storage library includes the picker, the pulley system placed within the U-shaped channel running along the vertical stack, and the drive shafts contained in the storage library modules. Thus, the robot assembly components are distributed across various parts of the storage library.
As indicated above, the distribution of the robot assembly components in various parts of the storage library is a problem because an error in the robot assembly may be anywhere within the storage library. For instance, the pulley system may not work, a drive shaft in a storage library module may have a problem, the picker may by malfunctioning, etc. As a result, someone with the capability of being able to dismantle and work inside the storage library, such as a service engineer, would be required to locate and fix the error.
Robot assembly components are some of the most frequently replaced components of a storage library. Consequently, requiring a service engineer to replace these components becomes expensive during the life of the storage library. It would be desirable if all of the robot assembly components were containable within a module located in one area of the storage library with this module enabling modular replacement and removal of all of the robot assembly components into and out of the storage library.
Another problem with the storage library disclosed in U.S. Pat. No. 5,870,245 is that capacity upgrades require additional robot assembly hardware. For example, the storage library of U.S. Pat. No. 5,870,245 is vertically expandable by inserting additional storage library modules into a rack. Each additional storage library module adds capacity to the storage library by adding more cartridges and/or drives. The storage library is at full capacity when the rack is full of storage library modules and cannot receive anymore. As noted above, each storage library module includes a picker drive shaft and the rear of the enclosures form a U-shaped channel which must be aligned. The pulley system may also have to be replaced with a larger pulley to support a capacity upgrade. As such, a capacity upgrade necessitates adding additional robot assembly hardware. It would be desirable if a capacity upgrade to a storage library did not require adding additional robot assembly hardware.